32v 1m cron

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CRON(1M) UNIX Programmer's Manual CRON(1M)


    cron - clock daemon




    _C_r_o_n executes commands at specified dates and times accord-
    ing to the instructions in the file /usr/lib/crontab.  Since
    _c_r_o_n never exits, it should only be executed once.  This is
    best done by running _c_r_o_n from the initialization process
    through the file /etc/rc; see _i_n_i_t(8).
    Crontab consists of lines of six fields each.  The fields
    are separated by spaces or tabs.  The first five are integer
    patterns to specify the minute (0-59), hour (0-23), day of
    the month (1-31), month of the year (1-12), and day of the
    week (1-7 with 1=monday).  Each of these patterns may con-
    tain a number in the range above; two numbers separated by a
    minus meaning a range inclusive; a list of numbers separated
    by commas meaning any of the numbers; or an asterisk meaning
    all legal values.  The sixth field is a string that is exe-
    cuted by the Shell at the specified times.  A percent char-
    acter in this field is translated to a new-line character.
    Only the first line (up to a % or end of line) of the com-
    mand field is executed by the Shell.  The other lines are
    made available to the command as standard input.
    Crontab is examined by _c_r_o_n every minute.